How To: Grin Cold-Storage Wallet

grin-cold-storage-wallet-howto.txt

These steps describe one possible method to create a grin wallet offline and add coins - i.e cold-storage.

1) Download the grin-wallet - either the executable or the source code and compile it into an executable
2) Partition and format a USB thumb drive (drive 1)
3) Copy the grin-wallet executable to the USB thumb drive 1
4) Copy a Grin TX slate file to the USB thumb drive 1
5) On a second USB thumb drive, or a CD/DVD, (drive 2) create a bootable image (https://linuxmint-installation-guide.readthedocs.io/en/latest/burn.html)
6) Unplug your network cable
7) Boot the image you created on drive 2
8) Insert and mount the drive with grin-wallet and slate file (drive 1)
9) Create a new wallet - Run "grin-wallet init"
10) Write down the seed words. Without these seed words your coins will be lost. 
11) Sign the slate file - Run "cd /mnt/drive1" and "grin-wallet receive -i slate_file"
12) Verify that you have the slate_file.response on thumb drive 1
13) Delete the wallet files - "rm -rf ~/.grin"
14) Unmount the USB thumb drive containing the grin-wallet executable and slate files
15) Shut down
16) Plug in your network cable
17) Boot your system as normal (not from the bootable thumb drive - drive 2)
18) Mount the USB drive with the slate files (drive 1)
19) Send the signed slate file (slate_file.response) back to the sender so they can finalize and broadcast the transaction.

Now the Grin blockchain has your coins, and you have the seed words necessary to generate a wallet that 
can claim and spend those coins.  Your wallet private key and seed phrase has never been on-line.

You can spend your coins using the following steps:
1) Download the latest grin node, and grin-wallet
2) Start the grin node and let it sync
3) Use the grin-wallet to re-create your wallet from the seed words
   The wallet will scan the blockchain and find your coins and they will be spendable now
ex: https://github.com/GrinPlusPlus/GrinPlusPlus/wiki/Restore-Wallet